Although the available state of the art devices have proved suitable for the purpose, they present defects and limitations which need to be eliminated. Devices are known, illustrated in U.S. Pat. No. 5,683,406, comprising a cutting edge positioned on the front side of a half moon-shaped aperture provided at the end of a slidable plate which closes a cavity in a handle, the purpose of which is to collect the shavings.
The cutting edge of said half moon-shaped aperture emerges on that side of the plate external to said cavity, and remains accessible from the outside in any position of the plate.
The handle cavity is closed by a slidable plate which uncovers the aperture for collecting the shavings which are formed by bringing said cutting edge into contact with the donor bone and sliding it along this latter while maintaining it pressed with a certain force.
This type of device presents a first defect deriving from the fact that the curved shape of the cutting edge intended to operate as a scraper makes it difficult to guide the instrument along the bone, in the sense that the cutting edge tends to deviate to the right or to the left of the path chosen by the surgeon.
Secondly, the pressure with which the cutting edge acts is determined essentially by the surgeon, with the double danger that the instrument may escape from his hand with the evident risk of cutting or lacerating the soft tissue close to the withdrawal region, and that excessive pressure may cause serious undesirable injury to blood vessels or, more dangerously, to nerves or tendons.
Finally, once used the device must be protected, because its cutting part remains exposed and can therefore accidentally wound whoever comes into contact with it, with the risk of infection.
An object of the invention is to eliminate said problems within the framework of a simple and economical construction.